Stabilized metal soap compositions



Patented Sept. 24, 1957 2,807,553 STABILIZED Marat soar coMPosirioNs Alfred Fischer, Bronx, N. Y., assignor, by mesne assignments, to Heyden Newport Chemical Corporation, a corporation of Delaware No Drawing. Application .Iuly 1a, 1955, Serial No. 522,865

lltl Claims. (Cl. ice-24s) This invention relates to oil-soluble metal salt or soap compositions useful in several arts for various purposes, such as, for example, paint and varnish driers, vinyl resin stabilizers, fungicides, catalysts, lubricant additives, bodying agents, etc.

The metal soaps useful alone or in combination as paint and varnish driers are principally the cobalt, manganese, lead, calcium, zinc, iron and vanadium soaps of certain organic acids. The fungicidal metal soaps include among others the soaps of copper, zinc, cadmium and mercury. Metal soaps useful alone or in combination as vinyl resin stabilizers are principally the soaps of barium, strontium, calcium, cadmium, zinc, tin and lead. Similar examples of metal soaps may be shown as being useful as catalysts, lubricant additives, etc. It also becomes apparent that a single metal in the form of its soap is useful in several applications. For example, zinc soaps are not only useful as driers, fungicides and vinyl resin stabilizers as previously stated, but also as pigment wetting agents, etc.

The metal soaps referred to are generally waterinsoluble solids. They are used commercially as solutions in non-polar, organic solvents, such as mineral spirits, Stoddards solvent, naphtha, kerosene, benzene, toluene, xylene and other solvents boiling at a temperature below 500 F. These solutions are added to the vehicle or organic medium for which they are intended. For example, cobalt, manganese and lead soaps are usually employed as driers in compositions containing drying oils and vehicles, such as linseed oil, oil-modified alkyd vehicles, etc. Barium, cadmium and zinc soaps may be employed as stabilizers for vinyl resin compositions containing plasticizers, such as dioctyl phthalate, dioctyl sebacate, tricresyl phosphate, etc. To be commercially useful, these metal soap solutions should dissolve easily, rapidly and with a simple mixing operation in the ultimate composition. Some of the other desirable physical characteristics of metal soap solutions upon which their commercial utility depends, are as follows:

1. They should be stable indefinitely in storage. Metal soap solutions usually are somewhat unstable and tend to precipitate during storage.

2. They should have a relatively low viscosity at high metal soap concentration so as to permit ready admixture with the vehicle or organic medium for which they are ultimately intended. In many cases, soap solutions at high metal concentration have an objectionably high viscosity and must be diluted to reduce viscosity. This means added cost as well as the incorporation of a larger proportion of extraneous material. In other cases, metal soap solutions which have an initially low viscosity tend to increase in viscosity on aging.

3. They should mix freely, quickly and easily at room temperature with the vehicles for which they are intended. Further, after they are incorporated into the ultimate compositions, they should notprecipitate during storage. Many soap solutions, even those of low viscosity, are incompletely soluble, or dissolve after a long period of time, or require vigorous and prolonged agitation to effect solution in the vehicle for which they are intended. Other soap solutions, after having dissolved in the ultimate vehicle or composition, sludge out during storage, that is, a portion of the active metal soap constituent precipitates and thereby becomes inactive.

Various attempts have been made in the past to obtain these desirable or ideal characteristics of metal soap solutions.v For example, the incorporation of free organic acid and certain alcohols have been suggested. However, their use is attcnded by many disadvantages such as volatility, relatively low degree of efficiency, adverse affects on the rate of drying in the case of the drying metal soaps, etc.

' The principal objects of this invention are to provide metal soap solutions which are of low viscosity, both initially and after aging,which are stable indefinitely, and which dissolve readily in the vehicles for which they are intended. Other objects and advantages of this invention will become evident as the description proceeds.

I have found as a result of protracted experimentation that the foregoing objects may be accomplished and that stabilized metal soap solutions may be provided by the incorporation in said solutions of polyoxyalkylene glycols of the formula H(OCHR1CHR2)OH, wherein R1 and R2 are either hydrogen atoms or alkyl groups and x equals at least 2. The polyoxyalkylene glycols of, this invention, when used to the extent of /2 part to 18 parts per parts of the metal soap solution, produce metal soap solutions of indefinite storage stability, of low viscosity, both initially and after aging, and of excellent solubility in vehicles, such as drying oils, e. g., linseed oil, plasticizers, e. g., dioctyl phthalate, etc. Some of the polyoxyalkylene glycols that I have successfully employed as stabilizing agents are diethylene, triethylene, tetraethylene, dipropylene, tripropylene and tetrapropylene glycols. I have found that, when x==3 in the foregoing formula, the glycols so described, namely, triethylene glycol and tripropylene glycol, are particularly effective in accomplishing the objects of this invention.

In addition, these triglycols improve the drying properties of cobalt, manganese, lead and calcium soaps and improve the stability of solutions of these drier soaps in linseed oil and other vehicles. While the mechanism by which these glycols operate is not as yet known, the particular efiectiveness of the triglycols suggest that the symmetrical structure of the latter, which may be written as follows is responsible, perhaps by forming complex compounds with the metal soaps.

The metals which may beemployed in the preparation of the metal soap solutions of this invention are the alkaline earth metals, e. g., barium, strontium, calcium, and the heavy metals, e. g., cobalt, manganese, lead, cadmium, iron, vanadium, zinc, nickel, tin, copper and mercury.

The organic acids which may be used with any of the foregoing metals to form the metal soap solutions of this invention include naphthenic acid, tall oil acids, rosin and rosin oil acids, unsaturated acids, such as oleic, linoleic and linolenic acids, and branch-chained saturated acids containing at least 8 carbon atoms, such as Z-ethylhexoic acid, isooctoic acid, etc. Combinations of the aforementioned acids, as well as other organic acids capable 'of forming oil-soluble metal soaps or salts, have been successfully employed in this invention. For the purposes of this invention and without distinguishing effect I have used the terms soap and salt synonymously.

The soaps resulting from the combination of the afore mentioned metals and organic acids may be dissolved in hydrocarbon solvents, such as mineral spirits and others previously mentioned, to form the metal soap solutions of this invention.

The following examples are given by way of illustration and notby limitation:

Example 1 A drier consisting of a solution of cobalt naphthenate in mineral spirits was prepared by a method well-known in the art, in which aqueous sodium naphthenate and cobalt sulfate undergo. a double decomposition reaction to form cobalt naphthenate which was dissolved in the mineral spirits solvent. The resulting solution contained approximately 6% cobalt metal. cobalt solution) of tripropylene glycol was added to the drier solution and the .mixture was heated to 250 F. to remove traces of water and to effect the solution of the tripropylene glycol. The resulting drier solution, after filtration, was found to be stable indefinitely, had a low viscosity, was readily soluble in linseed oil, and was very, etlective as a drier. r

The same cobalt drier, prepared without tripropylene glycol, the stabilizing agent, ,sludged and was only partially soluble inlinseed oil.

" Example 2 A cobalt tallate drier, containing approximately 6% cobalt metal and 3%v triethylene glycol was prepared in high flash naphtha according to the same method of Ex ample 1. The resulting 'drier was stable indefinitely, soluble in linseed oil, and had a low viscosity.

The cobalt tallate drier prepared without the triethylene glycol was very viscous and insoluble in linseed oil.

Example 3 A cobalt oleate drier, containing approximately 6% cobalt metal and 2% tetraethylene glycol was prepared in xylene according to the method of Example .1. The resulting drier had a low viscosity, was stable indefinitely and was readily soluble in linseed oil.

The cobalt oleate drier prepared without the stabilizing agent, tetraethylene glycol, was very viscous and insoluble in linseed oil.,

Example 4 A cobalt linoleate drier, containing approximately 6% cobalt metal and 3% dipropylene glycol was prepared in mineral spirits as in Example 1. The resulting drier had a low viscosity, was stable indefinitely and was read ily soluble in linseed oil.

The cobalt linoleate drier prepared without the dipropylenc glycol was very viscous and insoluble in linseed oil.

Example 5 A manganese drier consisting ,of a solution of manganese naphthenate in mineral spirits was prepared in the usual way by the double decomposition of sodium naphthenate and manganese sulfate. The resulting manganese naphthenate was dissolved in mineral spirits. 2% of triethylene glycol was added to the drier solution and the mixture was heated to 250 F. The resulting filtered solution was stable in storage, thin in viscosity, and readily soluble in linseedoil.

The same manganese drier, prepared without the stabilizing agent, triethylene glycol, was exceedingly viscous and insoluble in linseed oil.

Example 6 A manganese 2-ethylhexoate drier was prepared in the same manner. as in Example 5 by replacing sodium naphthenate with sodium 2-ethy1hexoate. 3% of tripropylene glycol was used in place of the 2% triethylene glycol of Example 3. The stabilized manganese 2-ethylhexoate drier that resulted was stable in storage, low in viscosity, and soluble in linseed oil.

4% (by weight of the r The same unstabilized manganese Z-ethylhexoate drier was viscous and insoluble in linseed oil.

Example 7 A lead drier consisting of a solution of lead naphthenate in Stoddards solvent was prepared in the usual way, well-known in the art, by reacting litharge with naphthenic acid. While still hot, 4 parts of tripropylene glycol to 24 parts of lead metal were added to the molten lead naphthenate. The reaction product was then dissolved in enough Stoddards solvent to make the lead concentration in the resulting solution 24%. The resulting filtered drier solution dissolved readily in linseed oil. The linseed oil solution showed no precipitate after several weeks.

The linseed oil solution of a lead drier prepared without the tripropylene glycol developed a precipitate in one day.

Example 8 A lead tallate was prepared in the same manner as in Example 7 by replacing naphthenic acid with tall oil acids. 4 parts of triethylene glycol were used in place of the 4 parts of tripropylene glycol of Example 7. The resulting stabilized drier was stable indefinitely at 0 F. and also at room temperature. A linseed oil solution of this lead drier showed no precipitate after several weeks. .The unstabilized lead tallate drier containing no trietbylene glycol precipitated immediately at 0 F. A linseed oil solution of the unstabilized lead tallate drier developed a precipitate in one hour.

Example 9 4 parts of diethylene glycol to 24 parts of lead metal were added to a lead oleate drier dissolved in mineral spirits. The resulting drier containing 24% lead metal dissolved readily in linseed oil and did not precipitate from the oil solution after several weeks.

. The unstabilized lead oleate developed a precipitate in one day after being dissolved in linseed oil.

Example J 0 8 parts of tripropylene glycol and 4 parts of triethylene glycol to 4 parts of calcium metal were added to a calcium naphthenate drier dissolved in mineral spirits. The resulting drier containing 4% calcium metal was of low viscosity, dissolved in linseed oil, and was found to be a highly effective drier.

The unstabilized calcium drier containing 4% calcium metal and no glycols was extremely viscous and insoluble in linseed oil.

Example 11 15 parts of tripropylene glycol to 5 parts of calcium metal were added to a solution of calcium 2-ethylhexoate in mineral spirits. The resulting soap solution containing 5% calcium metal had a low viscosity. It was suitable both as. a drier and a polyvinyl chloride resin stabilizer as it dissolved in linseed oil and dioctyl phthalate, a plasticizer commonly used with polyvinyl chloride.

The unstabilized calcium Z-ethylhexoate solution was extremely viscous and insoluble in both linseed oil and dioctyl phthalate.

Example 12 Triethylene glycol was dissolved in a mineral spirits solution of iron naphthenate so that the resulting drier contained 6% iron metal and 2% glycol. The stabilized drier was of low viscosity and soluble in linseed oil.

The unstabilized iron naphthenate drier was viscous and incompletely soluble in linseed oil.

Example 13 Tripropylene glycol was added to a mineral spirits solution of vanadium naphthenate so that the resulting drier contained 3% vanadium metal and 3% glycol.

The stabilized drier solution was low in viscosity and easily soluble in linseed oil.

The unstabilized vanadium drier was viscous and insoluble in linseed oil.

Example 14 Tetrapropylene glycol was added to a mineral spirits solution of nickel oleate so that the resulting drier contained 6 nickel metal and 4% glycol. The stabilized drier solution was low in viscosity.

The unstabilized nickel oleate solution was viscous.

Example 15 Triethylene glycol was added to a mineral spirits solution of zinc Z-ethylhexoate so that the resulting solution contained 12% zinc metal and 6% glycol. The stabilized zinc 2-ethylhexoate solution useful either as a drier or a vinyl resin stabilizer, had a very low viscosity.

The unstabilized zinc soap solution was extremely viscous.

Example 16 Tetraethylene glycol was added to a mineral spirits solution of zinc naphthenate so that the resulting solution contained 8% zinc metal and 2% glycol. The stabilized zinc naphthenate solution had a low viscosity.

The unstabilized zinc naphthenate solution was extremely viscous.

Example 17 Tripropylene glycol was added to a mineral spirits solution of barium 2-ethylhexoate so that the resulting solution contained 16% barium metal and glycol. The stabilized barium Z-ethylhexoate solution, useful as a polyvinyl chloride resin stabilizer, was low in viscosity, soluble in dioctyl phthalate, and stable indefinitely in storage.

The unstabilized barium soap solution was viscous, insoluble in dioctyl phthalate, and developed a crystalline precipitate after two days.

Example 18 Triethylene glycol was added to a mineral spirits solution of cadmium 2-ethylhexoate so that the resulting vinyl chloride resin stabilizer contained 14% cadmium metal and 5% glycol. The stabilized solution was low in viscosity and soluble in dioctyl phthalate.

The unstabilized cadmium soap solution was viscous and not completely soluble in dioctyl phthalate.

Example 19 Tripropylene glycol was added to a mineral spirits solution of copper naphthenate so that the resulting fungicide contained 8% copper and 2% glycol. The resulting stabilized soap solution had a low viscosity.

The unstabilized copper naphthenate solution was very viscous.

In the foregoing examples, some of the ways of combining the polyoxyalkylene glycols with the metal soaps have been defined, but it will be understood that the glycols may be combined with such metal soaps at any stage during their preparation or subsequent to the formation of the metal soaps. In practice, they may even be introduced into the metal soap-vehicle composition.

I have hereinbefore referred to different heavy metals and alkaline earth metals but have not attempted to give examples of all of said metals. However, the tests which have been made show very definitely that all of them may be employed in the carrying out of this invention. In many cases in the examples difierent metals may be substituted for those referred to therein, so that it has not been considered necessary to duplicate examples merely to show the employment of such different metals.

It will be apparent from the foregoing examples that the polyoxyalkylene glycols of this invention perform different functions. In some cases the function is singular in its nature while in other cases they perform a plurality of functions. Some of the several functions of the said polyoxyalkylene glycols may be briefly summarized as follows:

1. to render the metal soap solutions indefinitely stable,

2. to render metal soaps soluble in vehicles wherein they are insoluble in the absence of such glycols,

3. to improve materially the solubility of metal soap solutions in vehicles in which they are only partially soluble in the absence of such glycols,

4. to improve the stability of metal soap solutions in the vehicles for which they are intended,

5. to reduce the viscosity of unstabilized metal soap solutions, and,

6. to improve the effectiveness of metal soaps in their various end uses, e. g., to improve the drying properties of drying metal soaps.

In the foregoing description I have set forth the preferred embodiments of this invention but the examples herein given are to be understood as illustrative, only, and not as defining the limits of this invention which is to be understood as fully commensurate with the appended claims.

Having thus fully described the invention, what I claim as new and desire to secure by Letters Patent is:

l. A liquid composition consisting essentially of a solution of at least one water-insoluble soap of a metal selected from the group consisting of heavy metals and alkaline earth metals in at least one liquid hydrocarbon solvent for the soap, said solvent having a boiling point below 500 F., and at least one polyoxyalkylene glycol all in liquid state of the formula H(OCHR1CHR2)OH, wherein R1 and R2 are either hydrogen atoms or a hydrogen atom and a methyl group and x equals at least 2, said glycol being present to the extent of /218 parts by weight of the water-insoluble soap, said composition being a substantially anhydrous, homogeneous, stable liquid, mobile and free-flowing at room temperature.

2. A new composition according to claim 1, wherein the polyoxyalkylene glycol is polyethylene glycol.

3. A new composition according to claim 1, wherein the polyoxyalkylene glycol is polypropylene glycol.

4. A new composition according to claim 1, wherein the polyoxyalkylene glycol is triethylene glycol.

5. A new composition according to claim 1, wherein the polyoxyalkylene glycol is tripropylene glycol.

6. A new composition according to claim 10, wherein the polyoxyalkylene glycol is polyethylene glycol.

7. A new composition according to claim 10, wherein the polyoxyalkylene glycol is polypropylene glycol.

8. A new composition according to claim 10, wherein the polyoxyalkylene glycol is triethylene glycol.

9. A new composition according to claim 10, wherein the polyoxyalkylene glycol is tripropylene glycol.

10. A new composition according to claim 1, wherein the soap is the soap of a drying metal.

References Cited in the file of this patent UNITED STATES PATENTS 2,321,463 Condit June 8, 1943 2,425,828 Retzsch Aug. 19, 1947 2,465,961 Olphin Mar. 29, 1949 2,475,589 Bondi July 12, 1949 2,680,095 Hotten June 1, 1954 

1. A LIQUID COMPOSITION CONSISTING ESSENTIALLY OF A SOLUTION OF AT LEAST ONE WATER-INSOLUBLE SOAP OF A METAL SELECTED FROM THE GROUP CONSISTING OF HEAVY METALS AND ALKALINE EARTH METALS IN AT LEAST ONE LIQUID HYDROCARBON SOLVENT FOR THE SOAP, SAID SOLVENT HAVING A BOILING POINT BELOW 500*F., AND AT LEAST ONE POLYOXVALKYLENE GLYCOL ALL IN LIQUID STATE OF THE FORMULA H(CCHR1CHR2)XOH WHEREIN R1 AND R2 ARE EITHER HYDROGEN ATOMS OF A HYDROGEN ATOM AND A METHYL GROUP AND X EQUALS AT LEAST 2, SAID GLYCOL BEING PRESENT TO THE EXTENT OF 1/2-18 PARTS BY WEIGHT OF THE WATER-INSOLUBLE SOAP, SAID COMPOSITION BEING A SUBSTANTIALLY ANHYDROUS, HOMOGENEOUS, STABLE LIQUID, MOBILE AND FREE-FLOWING AT ROOM TEMPERATURE. 